Polling place

Polling place

Scott Olson / Getty Images

A sign marks the location of a polling place at the Greenbriar Mobile Home Park in Indianapolis, Indiana. For members of Congress facing tough reelection fights -- in North Carolina, Pennsylvania, Ohio, Florida and in Indiana -- political survival could depend on their choice and on which...

A sign marks the location of a polling place at the Greenbriar Mobile Home Park in Indianapolis, Indiana. For members of Congress facing tough reelection fights -- in North Carolina, Pennsylvania, Ohio, Florida and in Indiana -- political survival could depend on their choice and on which... (Scott Olson / Getty Images)

A sign marks the location of a polling place at the Greenbriar Mobile Home Park in Indianapolis, Indiana. For members of Congress facing tough reelection fights -- in North Carolina, Pennsylvania, Ohio, Florida and in Indiana -- political survival could depend on their choice and on which...Scott Olson / Getty Images